How do I use Boolean cuts to do this

I want to erase the outside portions of the circles only leaving behind the parts of the circle on the inside of the hexagon. I used MSPaint to draw what I mean:

BEFORE: http://i.imgur.com/3AqmUzY.png

AFTER: http://i.imgur.com/aqFapgQ.png

I tried every combo of Boolean operation possible and none came close to doing what I want. How do I get rid of those parts of the circles?

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It’s not just Booleans, there’s a lot of duplication which needs to happen, plus you’ll need to make certain certain objects are key objects.

First draw things up:

boolean_hex.c2d (8.0 KB)

Select the hexagon, note its position, duplicate it (control c) and restore the duplicate to the original location — do this 6 times.

Select a hexagon and an inner circle by clicking on on, then control-clicking on the other (why this is not shift click as in every other graphics program on the planet I’ll never understand — I didn’t realize CC had this feature because of this non-standard choice):

Apply the Boolean Intersection command — repeat 5 more times:

Select the hexagon, then a circle (the circle should have a dashed selection so as to indicate that it is the key object):

and choose Boolean Subtraction:

Repeat five times until done:

boolean_hex_done.c2d (368.6 KB)

c.f., https://shapeoko.com/wiki/index.php/Carbide_Create_Basics#Boolean_Operations

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So you would just use another copy of the hex to make it look like Brett’s drawing? Could you just lay that copy over the top of everything or would you have to do something special?

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If I may, you could also do this in Fusion 360 without the need for the booleans in a few steps. To do this in Fusion 360 required the following steps:
Draw the hex from the center point. A hex is the default polygon but it’s as simple as clicking on the center point and dragging out to get to your dimension. Then draw one of the arcs at a corner of the arc using the arc tool. Select that arc and use the offset tool to create a second copy where you want it. Then select both arcs and use the Circular Pattern tool. All you have to do is tell it how many copies you want and it places them automatically at each corner.
Now go to the CAM portion of F360, select the Engrave tool and click on each of the paths there (the 12 arcs and the one hex). Do the post process to build the gcode file. I just noticed I forgot your center circles, but that’s easy to do using the circle and offset tools.

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Oh, I thought it was supposed to come out.

Yes, in that case, dupe the hexagon 7 times so as to leave one unmodified copy.

Thanks for adding the instructions on doing this in Autodesk Fusion 360 — adding a link to it from the Commercial Software page.

Interestingly, I tried doing Will’s version (where the pie shapes float outside the hex) in Fusion 360 and after an hour, I gave up. I’m really new to CNC but you’d think you could just select the little piece of line between the two endpoints of the arcs and delete it. But, no, I could only select the entire line. But then, I thought, I could take the image and give it some depth and simply select the hex and the pies and extrude them. On the CAM side, I guess I’d just pocket the cutouts and leave a tab or two on each. I thought this was a very interesting exercise. Yeah, I know, I forgot the circles in the center again.

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Thanks a lot! This method worked out perfectly for me!

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